#include<stdio.h>
#include<pthread.h>
void *thread_summation(void *arg);
int sum=0;
//启动两个线程计算1到10的和
//通过加上-D_REENTRANT选项保证线程安全
int main(int argc,char *argv[])
{
	pthread_t id_t1,id_t2;
	int range1[]={1,5};
	int range2[]={6,10};
	pthread_create(&id_t1,NULL,thread_summation,(void *)range1);
	pthread_create(&id_t2,NULL,thread_summation,(void *)range2);

	pthread_join(id_t1,NULL);
	pthread_join(id_t2,NULL);
	printf("result:%d\n",sum);
	return 0;
}
void *thread_summation(void *arg)
{
	int start=((int*)arg)[0];
	int end=((int*)arg)[1];
	while(start<=end)
	{
		sum+=start;
		start++;
	}
	return NULL;
}
